自动编号与实体框架 [英] Autonumber with Entity Framework
问题描述
我要遍历对象的集合,他们都添加到表中。目标表有一个自动递增字段。如果我添加一个单一的对象是没有问题的。如果我想补充两个对象都为零的主键,实体框架失败。我可以手动指定主键,但尝试的EF整点是为了让生活更轻松不是更复杂。这里是code,并获得如下例外。
的foreach(在接触与我联系联系)
{
教师讲师= InstructorFromContact(接触);
context.AddToInstructors(讲师);
}尝试
{
context.SaveChanges();
}
赶上(异常前)
{
Console.WriteLine(ex.ToString());
}
该错误是:
System.InvalidOperationException :到数据库的变化成功提交,但在更新时发生错误
对象上下文。 ObjectContext中可能处于不一致的状态。
内部异常消息:AcceptChanges的无法继续,因为
对象的密钥值与另一个对象冲突
ObjectStateManager。确保键值是唯一的前
调用AcceptChanges的。在
System.Data.Objects.ObjectContext.SaveChanges(SaveOptions选项)结果
在System.Data.Objects.ObjectContext.SaveChanges()在
DataMigration.Program.CopyInstructors()的
C:\\项目\\ DataMigration \\的Program.cs:行52
块引用>解决方案在您的SSDL为自动增量字段设置StoreGeneratedPattern属性身份。它应该帮助。
I want to loop through a collection of objects and add them all to a table. The destination table has an auto-increment field. If I add a single object there is no problem. If I add two objects both with the primary key of zero, the entity framework fails. I can manually specify primary keys but the whole point of trying the EF was to make life easier not more complicated. Here is the code and the exception received follows.
foreach (Contact contact in contacts) { Instructor instructor = InstructorFromContact(contact); context.AddToInstructors(instructor); } try { context.SaveChanges(); } catch (Exception ex) { Console.WriteLine(ex.ToString()); }
The error is:
System.InvalidOperationException: The changes to the database were committed successfully, but an error occurred while updating the object context. The ObjectContext might be in an inconsistent state. Inner exception message: AcceptChanges cannot continue because the object's key values conflict with another object in the ObjectStateManager. Make sure that the key values are unique before calling AcceptChanges. at System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options)
at System.Data.Objects.ObjectContext.SaveChanges() at DataMigration.Program.CopyInstructors() in C:\Projects\DataMigration\Program.cs:line 52
解决方案Set the StoreGeneratedPattern attribute to "Identity" in your SSDL for the autoincrement field. It should help.
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